Some automobiles are provided with roof rails which extend along the length of a vehicle, one on each side. In order to carry items on the roof of such automobiles, crossbars (usually a pair thereof) are attached to the roof rails and roof boxes, or dedicated carriers for particular equipment (e.g. skis or bicycles) are attached to the crossbars.
A cross section through a conventional roof rail and crossbar is shown in FIG. 1. The roof rail 1 is formed of extruded aluminium and is of hollow cross section, with upper and lower chambers separated by a strengthening brace 2. From the sides of a lower plate 3 (for attachment to a roof), an upstanding inboard sidewall 4 and an upstanding outboard sidewall 5 extend. In the region of the brace 2, a projecting ridge 6 extends outwardly from the outboard sidewall 5. A sloping portion 7 then extends upwardly and inwardly from the outer edge of the projecting ridge 6, to meet the outboard edge of a flat top wall 8, which extends the majority of the width of the rail, as defined by the distance from the inner edge of the inboard sidewall 4 to the outer edge of the projecting ridge 6.
The crossbar 9 clamps onto the roof rail by means of a pair of resilient clamping jaws 10, 11. The inboard jaw 11 has a side portion 12, which extends along a portion of the length of the inboard wall 4, and has a top portion 13 which sits on the top wall 8 of the roof rail 1. The outboard jaw 10 has a side portion 14 which abuts the outer edge of the projection 6 and an inwardly extending portion 15 extending under the projection 6.
The side portions 12, 14 of the jaws 10, 11 clamp the roof rail between them, preventing it from moving back and forth, falling off or rattling. When the vehicle is stationary, force from the items carried by the crossbar is applied downwards onto the top wall 8 of the roof rail 1 via the top portion 13 of the inboard jaw 11. When the vehicle is in motion, an upward force can be applied by the items carried by the crossbar; this force is applied upward through the projection 6 via the inwardly extending portion 15.
Accordingly, the jaws 10, 11 clamp against much of the outer surface of the roof rail (in the portion along its length where they are attached), and hence the rail is a largely utilitarian part of the vehicle which is not easily finished with fragile decoration. Tough plastic covers, paint and decals may be applied to the surface of the roof rails, but all of these can be damaged by the jaws of the crossbar, or interfere with the strength of the clamping action of the jaws.
This invention seeks to provide a roof rail in which decorative features are not detrimental to the clamping action of the crossbar and/or are not damaged by the crossbar.